--- setup.py
+++ setup.py
@@ -178,28 +178,8 @@
 from distutils.errors import CCompilerError, DistutilsPlatformError
 from distutils.extension import Extension
 ext_modules = []
-try:
-    try:
-        from Cython.Distutils import build_ext
-        from Cython.Compiler.Version import version as pyrex_version
-    except ImportError:
-        print("No Cython, trying Pyrex...")
-        from Pyrex.Distutils import build_ext
-        from Pyrex.Compiler.Version import version as pyrex_version
-except ImportError:
-    have_pyrex = False
-    # try to build the extension from the prior generated source.
-    print("")
-    print("The python package 'Pyrex' is not available."
-          " If the .c files are available,")
-    print("they will be built,"
-          " but modifying the .pyx files will not rebuild them.")
-    print("")
-    from distutils.command.build_ext import build_ext
-else:
-    have_pyrex = True
-    pyrex_version_info = tuple(map(int, pyrex_version.rstrip("+").split('.')))
-
+have_pyrex = False
+from distutils.command.build_ext import build_ext
 
 class build_ext_if_possible(build_ext):